Strip cipher device



My 1 v J. w. M CLARAN 2,403,736

STRIP CIPHER DEVICE r Filed Nov. 28, 1932 2 Sheets-Sheet l 1, INVE TOR W7 7 gamm .m axm.

ATTDRNEY July 9, 194 6. J. w. MOCLARAN.

STRIP CIPHER DEVICE 2 Sheets-Sheet 2 Filed Nov. 28 1932 T k J mvENTohazz; MMs Ola/an li t *M rmom we...

YZXKLMNO IEADGHMNOR ISXMCGRATH xz mmo Uw JLNPRTVACEGI MQSTUVEFGHMQSUHJKLMNQ LNDCFHLMNOPRTUI FRANC IRSTXWYZFMIOCBDF ATTORNEYFIKLOIRTHIKLGHAD Patented July 9, 1946 NI ED" STAT es PATENT c erics- 7Claims.

This. lnvention'relates to a device for coding and; decoding messagesand. is of the typeemployingfa plurality of strips-each with one or morecomplete alphabets thereonearranged at random, all the alphabets on anystrip having the same sequential order, and pr-eierably with a differentsequence of letters on the various strips.

It is the' object-of this invention to provide amachine of the charactermentioned that is adapted to produce a -large number ofhighly complexcipher combinations without any sequence in the arrangement of theletters that is discov- V erableby onewho has not theke'ythereto.

With the aboveand other objects in view; the invention consists in theconstruction, combination-and arrangementof parts as willbefhereinaftermorefullydescribed; l v r In the-drawings 1 r Figure l" isa perspectiveviewo my invention; FigureZ-is'a bottom p'lanvie hereof;Figures 3; 4 and5 are respectively'atop plan view, a side 'elevatiomand"an end elevation of themeans usedfor connectingtlie ends ofthfe stripsthat -carryfthe alphabetyf Figure 6 is afde'tai'l-view of portionsofan'aIphabet strip;

Figure-7 shows an interrupterfor covering'certainof'the stripsifde'sired'; I

Fig: 8 is a plan "viewer the invention with parts broken away;illustrating the method of use.

The general-construction of my invention is shown in Figures 1 and 2.Feet Hi; which are preferably flexible rubber vacuum cups, carry aframe-"comprising longitudinal membersitconnected by a cross brace-12LPlate-I3--has anupper bracket I4 secured to each oftwocorners" and alower :bracket l5 fi-xed to each oftheother-two corners thereof, thebrackets l5 being'attached tomem'bers H andthe brackets being fastenedtouprights I 6 that are pivotally connected to the members1 l I topermit the disconnection of member: is from bracketswl lso the devicemay be foldedi l p Atthe lowerend of plate I3 is aseriesorindependentlyrotatable pulleys l1 mounted-on arcomia mon; shaftiand each having anoutwardly extending flange I8; preferably knurled, that. may be grasped:bythe thumb and fore-finger of the operator'jzo rotate: the pulley. Anequal number: of

pulleys I9, also independently-rotatable, are idist; posedrat theflipper-end of: plate l3 with pulleys I il -aligned with correspondingpulleys I 1,, wherebyarflexiblestrip 2ll-maybe passed aroundv the platel3 and over a pulley at each end. thereof.

Each strip 2fl=hasroni it-preferablytwo alpha- 5 (cits-#2) bets incwhiehtheiletters are inLthe same sequence, asishownini Figured, The :ends ofeach strip. are connected together by the connecting element shownin'Figurese3, Land 5 that has a substan tially tubular body portion 2 Iin which .is formed a longitudinal slot 2.2.. A hook 23 is connected tospring: 2am the body 2! which tends to draw the hookttowardnthe bodymember. A knob 25 istconnectedto the "spring'iand hook to move the hookaway from the body toirelease the hook from engagement with analphabetstrip. A resilient loop 26 haslaterally turned ends 21 that pass throughholes in theside of body member 2|, the loop being disconneotible fromthe body member by pressing: in the s ides of the loop. until the ends2! clear-the body member, and the loopis then withdrawn. At the hook endof body membertzl is-ta;- lug; 218; thatextends oppositely to knob 25with respect to body member 2|, The strip 20 has a looplat each end, oneof which is engaged by hook 23-and the other by loop 26 and the stripisikept -taut by spring 24. i

Spaced [rom the under sideof. plate I 3 is a to, brackets: 14 and 15. Analigning bar 30 is-slidably mounted; oniguides Z'Q and has a notch ineachen'drto receive a leg of ball 3 I, the1bail being sufficientlyresilient to permit bending it to removethe: legs thereof from the slotsinthe aligni-ng bar; The endszofbail 3| a-re' pivoted' at the rear endsof the members H and a spring 32 is connectedtoeach leg'of the bail andto the adjacent upright it un'der stress to tendto move the bail, andwith it the aligning bar 39, toward the upper end 'of platel3. A stop 33is fixed on each guide zeta limit the downward movement of aligningbarSDi A slide 34 is mounted to move over'the upper surface-of plate !3and has in it a slot 35 through which one letter on each strip 20 may beseen and thus defines a row of letters extending transversely of'platel3} A groove 36 is formed in slide 34 to receive an interrupter 31having cut-away portions 38'through which the letters on some of thestrips 2 maybe seen and solid portions-39 to cover certain other stripsAs many interrupters may be used as are desirable each of which has adifferent, arrangement of cut-away portions 33 and solid portions 39' toleave some of the. strips visible and cover other strips in anycombination.

While but one strip 29 is shown inposltion on the device-it is to beunderstood that there may be as many strips used as desired up to thefull number of pairs of pulleys l1 and IS.

The method of operation is as follows:

Before beginning the coding of a message the bail 3| is drawn toward theoperator which moves aligning bar 30 downwardly. The bar 30 is disposedto engage the lugs 28 on the strip connecting members and when furtherdownward movement of the bar is prevented by stops 33, all of the lugs28 will be aligned and the first letter in the alphabet sequence on eachstrip will be disposed under slot 35 in slide 34. The operator thenrotates the pulley I! at the left-hand side" of the device to turn thefirst letter of the message to be coded into position under slot 35,then the second pulley I! to bring the second letter of the message intoposition under the slot,

the third pulley I! to bring the third letter under the slot, and so onuntil each strip is so positioned that a letter thereon forms part of aword of the .message in a line visible through the slot 35. Slide34-isthen moved up along plate l3 to any desired position at which aline of letters will be visible through slot 35 but inasmuch as therandom sequences on the strips 20 are different, the letters thenvisible in slot 35.will not spell any word of the message. As shown byway of example in .Figure 8, the strips 20 have been moved to spell thewords Fleet sails today under slot 35; the

Slide is then moved up say thirteen letter spaces, and the meaninglesssequence DHIMORUHFHCI U VZ appears through slot 35 as shown in thedotted line position of slide 34. This is copied as part of the codemessage, Another line of letters that spell the succeeding part of themessage is then set under slot 35 when the slide is at the lower end ofthe plate. The slide is then moved up say thirteen letters and the codesequence recorded.

of the code message appear in slot 35 with slide -34 at its lowermostposition; the slide 34 is then moved up on plate l3 until there appearsin slot 35 a sequence of letters that spell words in plain language,which are recorded as a part of the decoded message. This is continueduntil all the letters of the coded message have been converted intoplain language. It is apparent that the person who decodes the messagemust have a key to inform him as'to the arrangement on the machine ofthe sequences used in coding.

The coded message may be rendered still more complicated by the use ofan interrupter or various interrupters under the slot 35. For example,in coding one message, or a part of one message, an interrupter having aspace to leave visible the first three strips, to cover the next five.strips, to leave visible four strips, to cover three strips and to showthe remaining strips, may be used,'and for a subsequent message, or partof a message, an interrupter that would have a different arrangement ofcut-away portions and solid portions may be inserted in groove 36. In

this case it is of course necessary that the person who decodes themessage must know the arrangement of the cut-away Portions and solidportions in the interrupter used in coding the message.

Various other means of complicating the code will suggest themselves tothose skilled in the art, such as settingthe letters of the message whencoding on a line other than that defined by slot 35 when slide 34 is inits lowermost position, etc.

It will be understood that the above description and accompanyingdrawings comprehend only the general and preferred embodiment of myinvention and that various changes in construction, proportion andarrangement of parts may be made within the scope of the appended claimswithout sacrificing any of the advantages of mv invention.

I claim:

1. In a device of the class described, a plate, supporting meanstherefor, a plurality of grooved pulleys at one end thereof, an equalnumber of grooved pulleys at the other end thereof, each of the lastmentioned pulleys being disposed to coact as one member of a pair with apulley at the other end of said plate and having an outwardly extendingflange whereb the pulley may be rotateda plurality of flexible stripspassing around said plate and over a pulley at each end thereof,resilient means connecting the ends of each strip and having anoutwardly extending lug, each said strip having on it two alphabets oneabove the other in the same random sequence but the sequence. on eachstrip being different .from that of any other strip, a slide movablelongitudinally of said plate having aslot through which a letter on eachstrip maybe seen, an .interrupter insertable in said slide to coverselectively any desired strip or strips, and means slidablelongitudinally of said plate to align all of said lugs. e I

'2. In a device of the class described, a plate, supporting meanstherefor, aplurality of grooved pulleys at one end thereof, an equalnumber of grooved pulleys at the other end thereof, alplurality offlexible strips passing around said plate and overa pulley at each endthereof, each said strip having on it two alphabets one above the otherin the same random sequence but the sequence on each strip beingdifferent from that on any other strip, a lug carried by each strip inthe same relative position, a slide movable longitudinally of said platehaving a slot through which a letter on each strip maybe seen, aninterrupter insertable in saidslide to cover selectively any desiredstrip. or strips, and means slidable longitudinally of said plate toalign all of said lugs. 7

3. In a device of the class described, a plate, ,a supporting frame tohold said plate in position, a plurality of grooved pulleys at one endthereof, an equal number of grooved pulleys at the other end thereof,a'plurality of flexible strips passing around said plate and over apulley at each end thereof, each said strip having on it two alphabetsone above the other in the same random sequence, a slide movablelongitudinally of said plate having a slotthrough which a letter on eachstrip may be seen, and an interrupter insertable in said slide to coverselectively any desired strip or strips. v

4. In a' device of the class described, a plate, supporting meanstherefor, a plurality of grooved pulleys at each end thereof, aplurality of flexible strips passing around said plate and over a.pulley at each end thereof, each said' strip having on it an alphabetarranged in random sequence, but the sequence on each strip beingdifferent from that on any other strip, a slide movable longitudinallyof said plate having a slot through which a letter on each strip may beseen, and an determined initial position and a slide movable 10longitudinally of said plate having a slot through which a letter oneach strip may be seen.

6. In a device of the class described, a plate, supporting meanstherefor, a plurality of pulleys at each end thereof, a plurality offlexible strips passing around said plate and over a pulley at 6 eachend thereof, each said strip having on it an alphabet arranged in randomsequence, means to move all of said strips simultaneously to apredetermined initial position and means to define a transverse lineacross said plate.

'7. In a device of the class described having a frame, aligning meanscomprising parallel guides at opposite sides of said frame, a straightedge slidably mounted on said guides, a bail pivoted at its ends toopposite sides'of said frame and engaging said straight edge to slidethe straight edge on said guides and resilient means tending to holdsaid bail at one end of said frame to maintain said straight edge atsaid end except when 15 moved by an operator.

JOHN W. MCCLARAN.

